1. Field of the Invention
The present invention relates to a method in a data processing system for creating, registering and managing a document or program, wherein the method includes determining whether or not the content of stored data consisting of a plurality of blocks of data (data elements) is a valid data block which remains as created and stored by the authorized user, for each data element, and detecting that an improper rewrite has been made, if such is the case.
2. Related Background Art
It is conventionally common practice that a document is created on a computer, and stored as a file.
When this document file is used in joint work by a plurality of users, a method has been adopted in which under the operating system, the file is shared among the plurality of users and other users are inhibited from gaining access to the file.
For example, in a UNIX operating system, permission for writing, reference (reading), and execution can be given to the owner of the file, the group involved in the joint work, and other users, for each file.
In such a system, when a certain file is shared within a group, and users outside of the group are inhibited from changing the file, a method is taken in which the users within the group are permitted to write into the file, but those users outside of the group are inhibited from writing, so that the file can be shared only within the group.
When one document is created by a plurality of persons taking over different portions of the work, it is divided into separate files assigned to the respective persons in charge (objects of management), in which each separate file is managed by the respective person in charge, so that others are inhibited from writing in the portion assigned to that person in charge.
However, with the conventional example, permission for writing in or reading a file is only given to the owner of the file, the group and other users. Also, the justification of the document can be assured by inhibiting unauthorized users from writing. Accordingly, since such management can only be performed file by file, there were the following associated problems.
1. When a document file created by each of a plurality of persons is a part of one collective document to be created jointly, the files may not be unified into one file, so that the document cannot be dealt with collectively.
2. It is not possible to meet a requirement of recognizing when a rewrite has occurred, although rewriting by others is permitted.
3. When the rewrite by superuser (a user having all rights for any file) or a false rewrite by a authorized user is made, there is no indication of the alteration.